Slashdot Mirror
English Market Produces Energy With Kinetic Plates
Johnathan Martinez writes "Sainsbury's market in England has installed 'kinetic energy' plates in the parking lot of its store in Gloucester. The plates are an experiment with a newer energy producing technology. The plates create as much as 30 kWh of energy as cars drive over them. The weight of the cars puts pressure on the plates creating kinetic energy to run a generator. The current is used to power the store and will lower the energy consumption of the market."
This is just an gas powered electric generator, the likes of which rube goldberg would be proud of. You'd be better off siphoning a thimble of fuel from each car, selling it, and using the proceeds to buy electricity from the utility.
is that energy extracted from the cars? then is not magically created, but just a inefficient way to suck energy from other people use of oil.
-Woof woof woof!
***face palm***
Sigh.
Ok, that's like saying you increase your fuel mileage by driving down hill. What you are failing to take into account is that all your gains have been lost when it comes time to drive back up it! It's the same idea with these plates, but on a much much smaller scale.
Life is not for the lazy.
As many other commented, the energy comes off course from the petrol engine of the cars. 1. The efficiency of this system from petrol to electricity must be really low 2. It creates pollution right where you don't want it, in the city: Exhaust fumes plus tire wear
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TFA calls it a "green energy project". The type of people who think this is green energy are the complete f-ing morons that side track the rest of us from real viable energy advancements.
Further more, the TFA claims this will "lower the energy consumption of the market". At the inefficiency of this (which is already limited to being no more efficient than a car is itself), it will actually increase the energy consumption of the market.
The whores get mad when the sluts give it away for free.
Except they wouldn't have since energy has to come from somewhere and car's don't magically use it for no purpose. The energy they're using comes from raising the car's height (ie: potential energy due to gravity) to the height of the plate. Without the plate that energy would not have been used period as there'd have been no need to raise the car's height.
Had there been a natural downward slope present (say it was a speed bump, small hill, etc.) then the energy would have been partially reclaimed and converted into kinetic energy for the car. In other words going downhill makes the car go faster and that energy came from when the car had to go up the hill.
Probably 2/3 of the comments so far seem to think this is some kind of perpetual motion machine con. Those people should be embarrassed.
It's not. It's simple. It's just slowing cars by converting kinetic energy into electrical, instead of dissipating it as heat in the brakes or converting it to potential energy like a speed bump.
There was a discussion a while back, I think here on Slashdot, about a device that used a revolving door to generate energy. It prompted exactly the same comments. What these people didn't seem to realize is, revolving doors have brakes, and that device replaces the brakes. Same damn thing.
Do you really think the engineers who designed this device didn't think it through? This reminds me why it's never a good idea to discuss physics on Slashdot. I leave it to psychologists to explain why there are so many kneejerk contrarians.
No. But afterwards, if you didn't give the engine any gas during the process, it would be moving slower. As lots of people have tried to point out, this might be desirable (see speed bumps). If the driver is just going to accelerate back to speed however, you have gained nothing.
I think that for this calculation to be reasonable you need to know the actual fuel usage while maintaining 100kph on a flat highway with no wind. I suspect that it is higher than 18 km/l, that sounds more like a rated highway fuel efficiency number which probably includes a lot more than just maintaining speed on a flat level road.
My 0.1 m/s^2 deceleration for a 900kg car shows a drag force (wheels + air + differential + bearings + exit shaft of gearbox) on the car of 90N. I don't need to know where that 90N is coming from.
So I don't see why I can't do what I did. I think it's completely valid.